1. Technical Field
The present invention relates to a technique for processing a sound signal.
2. Background Art
In audio compression, such as MP3 (MPEG-1 Audio Layer III) or AAC (Advanced Audio Coding), since the band components in a high-tone band and a low-tone band of a sound signal are removed (i.e., band limiting), there is a problem in that the sound quality of reproduced sound is degraded. As a technique for suppressing degradation of sound quality due to band limiting, for example, JP-A-2007-178675 discloses processing (hereinafter, referred to as “band expansion processing”) for reinforcing a high-tone band and a low-tone band using specified band components of a sound signal.